Shopping for a bargain? Bookmark these sites

That's why so many websites promise to help you save money and snag super deals. The editors at Consumer Reports ShopSmart magazine are always looking for great new money-saving sites and they found four that you might want to visit and bookmark.

Checkout51.com offers a cash-back reward program for supermarket shoppers. Visit the site, check out the weekly offers—they're updated every Thursday—and see if there's anything on the list that you plan to buy. For example, earn 50 cents on Ken's Ranch dressing, $1.00 on Windex or $1.50 on Pledge.

Shop at any store and when you're done, upload a picture of your receipt. When you hit $20 in rewards, they send you a check.

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What do they do with all the information they gather from those receipts? Checkout51 says its partners can use it to provide you with "customized offers and messages," although the privacy policy states that these partners never receive your name, mailing address or email address.

Chippmunk.com (yes, with two p's) is a new coupon-code search engine that lets you search by retailer or merchandise (from accessories to wine) or price.

You can sort those results by the type of discount—coupon codes, sales or free shipping—and they're automatically ranked from most to least savings. There are also filters you won't find on other coupon sites, such as ways to pay, estimated shipping time and who has in-store pickup.

"We were really impressed with the simplicity of the site," said ShopSmart deputy editor Jody Rohlena. "It's easy to use and we also felt like there was a really good variety to the codes."

Nifti.com offers pages and pages of items for sale, but that's not what makes this site special. You can ask it to track the price for one of those featured items or for some other product you choose at another website. It works on hundreds of well-known retail sites, including Amazon.com.

Just drag the Nifti button to your browser's bookmark bar. When you're on another site and find an item you like, click the Nifti Button, set the price you want to pay and it will constantly search for you. If the price drops below your desired price, you'll get an email.

You can also use Nifti to track price changes over time. So for instance, if the price trend is downward, you might want to wait a little bit longer, to see if it drops even more.

Swapdom.com has come up with a creative way to let you get stuff for free through organized swapping. Upload pictures and descriptions of what you want to swap. Then select what you want from the items already posted and list what you're willing to offer in exchange.

"It sounds a little complicated," Rohlena said, "but once you say what you want and what you're willing to get rid of, they do all the work."

The site uses an algorithm to organize a "circle swap"—an exchange that involves multiple people—so that everyone gets what they want. You don't have to bargain or negotiate. Swapdom says it's designed to make sure everyone gets a fair trade.

You do have to pay for shipping, plus a small fee to the site that is never more than $2. Right now, there are just two categories: clothing and kids' gear. Home décor is supposed to be added soon.

The best search engine

We all know how easy it is to comparison shop using a search engine. ShopSmart found that it's really important to choose the right one if you want to consistently find the lowest prices.

They shopped for five items—a hardcover book, sports bra, kitchen mixer, digital camera and HD TV—on eight major search engines. The price differences between the sites were often dramatic. The winner: Google.com/Shopping.

"Google's price comparison function really works beautifully," Rohlena told me. "It's simple and it came up with the lowest total bill on our list of items that we were pricing."

PriceGrabber.com, a site the editors at Consumer Reports have recommended in the past, was a close second.